They did show his rise to power tho.
Marlo just had a few corners when we first meet him. He's a nobody. Then those towers came down and Barksdale had to expand out into new territory. They approached the dealers who occupied those corners and most got down cuz a) They were the mighty Barksdale crew and b) they came with a good deal. Marlo was the only holdout. He was like a young Avon... he didn't give a fukk how good of a deal String presented, those were his corners and he was gonna hold them.
His rise to power was valiantly holding those corners then shrewdly taking down half the city which was gift wrapped for him by String and Joe (the co-op).
